Summary of Fair Value of Convertible Note Redemption Provision Derivative Liability (Detail) - USD ($) $ in Thousands	3 Months Ended
Aug. 31, 2020	Aug. 31, 2019
Net Proceeds	$ 25,000
Derivative Liability		1,443
Convertible Note Redemption Provision Derivative Liability [Member] \| Inception date June 2018 Note, November 15, 2018 [Member]
Net Proceeds	5,000
Inception Date	1,285
Derivative Liability		373
Convertible Note Redemption Provision Derivative Liability [Member] \| Inception date January 2019 Note, January 30, 2019 [Member]
Net Proceeds	5,000
Inception Date	$ 1,465
Derivative Liability		$ 1,070

Amount of embedded derivative liability as on inception date.

No definition available.

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- Definition

Fair value as of the balance sheet date of the embedded derivative or group of embedded derivatives classified as a liability.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4B
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5624163-113959

+ Details

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- Definition

The cash inflow from the issuance of a long-term debt instrument which can be exchanged for a specified amount of another security, typically the entity's common stock, at the option of the issuer or the holder.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3255-108585

+ Details

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- Details

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- Details

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